======================================
| [   20.007073][    C2] 1 lock held by ksoftirqd/2/27:
| [ 20.007248][ C2] #0: ffffffffbd1774c0 (rcu_callback){....}-{0:0}, at: rcu_do_batch (./include/linux/rcupdate.h:331 kernel/rcu/tree.c:2570) 
| [   20.007564][    C2]
| [   20.007564][    C2] stack backtrace:
[   20.007850][    C2] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   20.007853][    C2] Call Trace:
[   20.007856][    C2]  <TASK>
[ 20.007860][ C2] dump_stack_lvl (lib/dump_stack.c:123) 
[ 20.007869][ C2] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 20.007877][ C2] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 20.007885][ C2] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 20.007892][ C2] ? save_trace (kernel/locking/lockdep.c:595) 
[ 20.007901][ C2] mark_lock (kernel/locking/lockdep.c:4756) 
[ 20.007906][ C2] mark_usage (kernel/locking/lockdep.c:4645) 
[ 20.007910][ C2] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 20.007915][ C2] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 20.007920][ C2] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 20.007925][ C2] ? simple_pin_fs (fs/libfs.c:1067) 
[ 20.007931][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 20.007936][ C2] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 20.007940][ C2] ? simple_pin_fs (fs/libfs.c:1067) 
[ 20.007948][ C2] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 20.007953][ C2] ? simple_pin_fs (fs/libfs.c:1067) 
[ 20.007957][ C2] simple_pin_fs (fs/libfs.c:1067) 
[ 20.007964][ C2] debugfs_remove (fs/debugfs/inode.c:805 fs/debugfs/inode.c:799) 
[ 20.007970][ C2] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 20.007978][ C2] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 20.007984][ C2] ? __sk_destruct (./include/linux/instrumented.h:96 ./include/linux/atomic/atomic-instrumented.h:400 ./include/linux/refcount.h:389 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/net_namespace.h:287 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 20.007992][ C2] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 20.007997][ C2] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 20.008002][ C2] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 20.008009][ C2] ? kthread (kernel/kthread.c:464) 
[ 20.008013][ C2] ? ret_from_fork (arch/x86/kernel/process.c:148) 
[ 20.008019][ C2] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 20.008026][ C2] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2427) 
[ 20.008032][ C2] ? __pfx_migrate_enable (kernel/sched/core.c:2402) 
[ 20.008039][ C2] __put_net (net/core/net_namespace.c:732) 
[ 20.008045][ C2] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 20.008051][ C2] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 20.008056][ C2] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 20.008062][ C2] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 20.008069][ C2] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 20.008072][ C2] ? __pfx_tmigr_handle_remote (kernel/time/timer_migration.c:1059) 
[ 20.008079][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 20.008084][ C2] ? note_gp_changes (kernel/rcu/tree.c:1326 (discriminator 1)) 
[ 20.008088][ C2] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 20.008095][ C2] rcu_core (kernel/rcu/tree.c:2834) 
[ 20.008101][ C2] handle_softirqs (kernel/softirq.c:579) 
[ 20.008108][ C2] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 20.008113][ C2] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 20.008116][ C2] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 20.008122][ C2] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 20.008127][ C2] kthread (kernel/kthread.c:464) 
[ 20.008132][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 20.008136][ C2] ? ret_from_fork (arch/x86/kernel/process.c:147) 
[ 20.008140][ C2] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 20.008146][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 20.008151][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 20.008156][ C2] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 20.008161][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 20.008165][ C2] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
| [   20.022793][    C2] RCU nest depth: 0, expected: 0
| [   20.022977][    C2] INFO: lockdep is turned off.
| [   20.023145][    C2] Preemption disabled at:
| [ 20.023147][ C2] handle_softirqs (kernel/softirq.c:553) 
[   20.023510][    C2] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   20.023513][    C2] Call Trace:
[   20.023516][    C2]  <TASK>
[ 20.023520][ C2] dump_stack_lvl (lib/dump_stack.c:123) 
[ 20.023529][ C2] __might_resched (kernel/sched/core.c:8796) 
[ 20.023536][ C2] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 20.023540][ C2] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 20.023543][ C2] ? simple_recursive_removal (fs/libfs.c:614) 
[ 20.023547][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 20.023552][ C2] ? do_raw_spin_unlock (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141) 
[ 20.023558][ C2] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 20.023561][ C2] ? do_raw_spin_unlock (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141) 
[ 20.023564][ C2] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 20.023570][ C2] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 20.023573][ C2] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 20.023579][ C2] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 20.023583][ C2] ? __sk_destruct (./include/linux/instrumented.h:96 ./include/linux/atomic/atomic-instrumented.h:400 ./include/linux/refcount.h:389 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/net_namespace.h:287 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 20.023589][ C2] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 20.023592][ C2] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 20.023595][ C2] ? smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 20.023599][ C2] ? kthread (kernel/kthread.c:464) 
[ 20.023602][ C2] ? ret_from_fork (arch/x86/kernel/process.c:148) 
[ 20.023606][ C2] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
[ 20.023612][ C2] ? migrate_enable (./arch/x86/include/asm/preempt.h:104 ./include/linux/preempt.h:481 ./include/linux/preempt.h:481 kernel/sched/core.c:2427) 
[ 20.023616][ C2] ? __pfx_migrate_enable (kernel/sched/core.c:2402) 
[ 20.023621][ C2] __put_net (net/core/net_namespace.c:732) 
[ 20.023625][ C2] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 20.023629][ C2] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 20.023632][ C2] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 20.023635][ C2] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 20.023639][ C2] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 20.023641][ C2] ? __pfx_tmigr_handle_remote (kernel/time/timer_migration.c:1059) 
[ 20.023646][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 20.023649][ C2] ? note_gp_changes (kernel/rcu/tree.c:1326 (discriminator 1)) 
[ 20.023652][ C2] ? lockdep_hardirqs_on (kernel/locking/lockdep.c:4475) 
[ 20.023656][ C2] rcu_core (kernel/rcu/tree.c:2834) 
[ 20.023660][ C2] handle_softirqs (kernel/softirq.c:579) 
[ 20.023664][ C2] ? __pfx_run_ksoftirqd (kernel/softirq.c:961) 
[ 20.023667][ C2] run_ksoftirqd (kernel/softirq.c:436 kernel/softirq.c:969 kernel/softirq.c:960) 
[ 20.023670][ C2] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 20.023674][ C2] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 20.023678][ C2] kthread (kernel/kthread.c:464) 
[ 20.023681][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 20.023683][ C2] ? ret_from_fork (arch/x86/kernel/process.c:147) 
[ 20.023686][ C2] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 20.023689][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 20.023692][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 20.023695][ C2] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 20.023698][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 20.023700][ C2] ret_from_fork_asm (arch/x86/entry/entry_64.S:258) 
| [   23.818277][    C2] INFO: lockdep is turned off.
| [   23.818501][    C2] Preemption disabled at:
| [ 23.818503][ C2] 0x0 
| [   23.818978][    C2] Tainted: [W]=WARN
[   23.818979][    C2] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   23.818981][    C2] Call Trace:
[   23.818984][    C2]  <IRQ>
[ 23.818986][ C2] dump_stack_lvl (lib/dump_stack.c:123) 
[ 23.818997][ C2] __might_resched (kernel/sched/core.c:8796) 
[ 23.819008][ C2] down_write (./include/linux/kernel.h:73 kernel/locking/rwsem.c:1576) 
[ 23.819014][ C2] ? __pfx_down_write (kernel/locking/rwsem.c:1575) 
[ 23.819018][ C2] ? simple_recursive_removal (fs/libfs.c:614) 
[ 23.819022][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 23.819028][ C2] ? do_raw_spin_unlock (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141) 
[ 23.819034][ C2] simple_recursive_removal (./include/linux/dcache.h:409 ./include/linux/dcache.h:424 ./include/linux/dcache.h:434 fs/libfs.c:617) 
[ 23.819037][ C2] ? do_raw_spin_unlock (./arch/x86/include/asm/atomic.h:23 ./include/linux/atomic/atomic-arch-fallback.h:457 ./include/linux/atomic/atomic-instrumented.h:33 ./include/asm-generic/qspinlock.h:57 kernel/locking/spinlock_debug.c:101 kernel/locking/spinlock_debug.c:141) 
[ 23.819040][ C2] ? __pfx_remove_one (fs/debugfs/inode.c:780) 
[ 23.819046][ C2] debugfs_remove (fs/debugfs/inode.c:806 fs/debugfs/inode.c:799) 
[ 23.819049][ C2] ref_tracker_dir_exit (lib/ref_tracker.c:411 lib/ref_tracker.c:195) 
[ 23.819055][ C2] ? __pfx_ref_tracker_free (lib/ref_tracker.c:253) 
[ 23.819058][ C2] ? __sk_destruct (./include/linux/instrumented.h:96 ./include/linux/atomic/atomic-instrumented.h:400 ./include/linux/refcount.h:389 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/net_namespace.h:287 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 23.819064][ C2] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 23.819067][ C2] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:189) 
[ 23.819071][ C2] ? irq_exit_rcu (kernel/softirq.c:698) 
[ 23.819075][ C2] ? sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[ 23.819081][ C2] ? asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 23.819085][ C2] ? pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 23.819088][ C2] ? default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 23.819091][ C2] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 23.819095][ C2] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 23.819100][ C2] ? do_idle (kernel/sched/idle.c:325) 
[ 23.819103][ C2] ? cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 23.819108][ C2] ? start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 23.819113][ C2] ? common_startup_64 (arch/x86/kernel/head_64.S:419) 
[ 23.819119][ C2] ? bpf_sk_storage_free (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:871 net/core/bpf_sk_storage.c:61) 
[ 23.819123][ C2] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 23.819127][ C2] __put_net (net/core/net_namespace.c:732) 
[ 23.819130][ C2] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2376) 
[ 23.819135][ C2] ? rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 23.819137][ C2] rcu_do_batch (kernel/rcu/tree.c:2576) 
[ 23.819142][ C2] ? __pfx_rcu_do_batch (kernel/rcu/tree.c:2500) 
[ 23.819145][ C2] ? trace_irq_enable.constprop.0 (./include/trace/events/preemptirq.h:40) 
[ 23.819151][ C2] ? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/preempt.h:104 ./include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194) 
[ 23.819156][ C2] rcu_core (kernel/rcu/tree.c:2834) 
[ 23.819162][ C2] handle_softirqs (kernel/softirq.c:579) 
[ 23.819171][ C2] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 23.819176][ C2] irq_exit_rcu (kernel/softirq.c:698) 
[ 23.819180][ C2] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[   23.819185][    C2]  </IRQ>
[   23.819187][    C2]  <TASK>
[ 23.819188][ C2] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 23.819191][ C2] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 23.819195][ C2] Code: a2 b5 00 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 83 47 10 00 fb f4 <e9> fc 54 02 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
All code
========
   0:	a2 b5 00 c3 cc cc cc 	movabs %al,0xfccccccccc300b5
   7:	cc 0f 
   9:	1f                   	(bad)
   a:	00 90 90 90 90 90    	add    %dl,-0x6f6f6f70(%rax)
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	0f 00 2d 83 47 10 00 	verw   0x104783(%rip)        # 0x1047ab
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	e9 fc 54 02 00       	jmp    0x2552b		<-- trapping instruction
  2f:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  36:	00 00 00 
  39:	66 90                	xchg   %ax,%ax
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Code starting with the faulting instruction
===========================================
   0:	e9 fc 54 02 00       	jmp    0x25501
   5:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
   c:	00 00 00 
   f:	66 90                	xchg   %ax,%ax
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
[   23.819198][    C2] RSP: 0018:ffffc90000147de8 EFLAGS: 00000246
[   23.819202][    C2] RAX: 0000000000000002 RBX: 1ffff92000028fc1 RCX: ffffffffbc18f5d9
[   23.819204][    C2] RDX: ffffed1005ee66fb RSI: ffffffffbc453b60 RDI: ffffffffb998d18f
[   23.819206][    C2] RBP: 0000000000000000 R08: 0000000000000000 R09: ffffed1005ee66fa
[   23.819207][    C2] R10: ffff88802f7337d3 R11: ffff888008814ad8 R12: 0000000000000000
[   23.819209][    C2] R13: ffff888001bf2300 R14: dffffc0000000000 R15: 0000000000000000
[ 23.819213][ C2] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 23.819216][ C2] ? cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 23.819220][ C2] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 23.819222][ C2] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 23.819225][ C2] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 23.819228][ C2] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 23.819232][ C2] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 23.819236][ C2] do_idle (kernel/sched/idle.c:325) 
[ 23.819240][ C2] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 23.819243][ C2] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 23.819246][ C2] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 


Finger prints:
__might_resched:down_write:simple_recursive_removal:debugfs_remove:ref_tracker_dir_exit
mark_lock_irq:mark_lock:mark_usage:__lock_acquire:_raw_spin_lock
handle_softirqs:dump_stack_lvl:__might_resched:down_write:simple_recursive_removal